Hmm...okay. I just skipped over the 'modify any wii 4.2 & below' thread, but I must say that it doesn't install any programs you don't want or need.

Can you do it with less than in the guide? Technically...yes. But if you check these forums, you'll find that almost everyday, someone comes crying that their wii got bricked and that they don't have a means to restore things.

The problem is usually not due to these people being too dumb to mess with their wii, but because they followed a (often outdated) guide half-heartedly and didn't took caution until it was too late.

Let's see what the guide covers (a bit of an overview of the steps)
-safely update to 4.2. This is important because the 4.2 update removes all homebrew -> skip this part, and every disc update can be your last one (recent example).
-bannerbomb: simply crucial to get started. No way around it
-the homebrew channel: while technically not required, it is HIGHLY advised. The reason: it makes the other steps and homebrewing about 100x easier. If nothing else, I suggest you try it until you're completely done with the guide. If you still want to remove it then, you can also do so easily (it's only 1 channel that takes up only a few blocks).
-DVDX: as mentioned, this can be skipped without problems
-bootmii: this program allows you to make full backups of your wii's hard drive. As with the homebrew channel, you don't HAVE to install it. And if all goes well, you'll never need it. The thing is...if something goes totally wrong, this proggie (and a backup made by it) is what you need to get things back the way they were.
-priiloader: while you may not NEED it (unless you're planning to use out-of-region games), it's still a good tool that'll prove it's worth easily. If you couldn't install bootmii as boot2 (depends on the model of your wii), it's just as crucial as bootmii itself.
-Multi-Mod Manager: not really crucial by itself, but it's purpose in the guide (restoring the trucha bug) is. So...just install it and follow the rest of the guide. You can uninstall MMM afterward if you have to.

Beyond that, it's a matter of how you want to play backups. Do you want to run them from an USB-drive or from discs? Either way, it'll mean installing even more stuff.

EDIT: 3 new posts since I made mine.
The zip is just to have all the mentioned programs in one bundle. All of those programs can be found individually by searching on this forum as well.

That "IOS thing" is most likely cioscorp (or darkcorp, which is the latest version of it). It basically patches everything under the hood (including trucha patching) to allow backup discs to be played through the disc channel.
In normal cases, that should be sufficient. But future proof-ness is always a bit tricky. Though darkcorp currently works great*, it's hard to predict whether it'll handle games like super mario galaxy 2 (which'll ship next month). Or a future firmware.

*note: keep in mind that the newer kinds of wii's have a different DVD-drive that simply can't use backup discs.

1) exactly
2) not at all. priiloader is mostly a program that puts itself in the boot sequence before the loading of the actual wii menu. As such, it can enable a whole array of hacks. You can use it to set your wii to load directly into the homebrew channel or bootmii, set it to not having to press "A" at the health screen, prevent unwanted updates, ignore region-bound settings and a whole lot of other things.
3) did you check the link to the complete softmod guide? It has a whole section about the trucha bug.
4) Yes...because it would make you lazy. Get used to searching for things. You might learn something in the process.
5) the video starts with "there is a Risk that you could brick the wii EVEN if you do everything right". I haven't watched the whole thing, but at first glance, it seems pretty much up to par with what's in the sticky.
If, however, you're just fishing for someone to take responsibility for you taking actions on your wii, I must say...you're not going to find anyone here. Everything you do is at your own risk. It's up to you to take that risk, along with any success or failure it'll bring.

EDIT: just noticed that preloader's in the video (priiloader's the successor to preloader). That, and the fact that the first youtube-reply is from the author warning yet again that it won't work on all wii's, means I'd advise to stick to the sticky guide over that video (it's also more recently updated, by the way).

You'll need a bit more than 500 MB free space on your SD card for a full backup. It'll contain 2 files (nand.bin and keys.bin, iirc). You can store these files anywhere you want; just remember that if you want to restore them, you'll need to place them back in the root of your SD-card.

Other info should be explained pretty straightforward in the complete softmode guide. (there's a reason why it's called "complete" ). Since bootmii (as boot2) is loaded before anything else, it will still load no matter what you do with the software on your wii.
With bootmii as IOS, you're a bit less overall-protected (but still quite safe). You should still be able to enter bootmii by first loading priiloader (which is started by holding down the reset button while powering on the wii), and then choosing "load bootmii".

EDIT: an extra note: bootmii runs before the initialisation of the wiimote. As such, wiimotes don't work. You navigate the menu with the power- and the reset-buttons.

no,it's exactly the same as the original 256 sd card,but for some reason it doesn't recognize it!
I have 2 adapters,one for micro and one for mini and they both stick inside the slot! the wii doesn't recognize any of them but it DID recognize the standard 256mb sd card.

the card needs some pushing to get it in because it's resisting for some wierd reason...after it's all the way in,you normally would push it in a bit and it would pop out.but it's not the case with these adapters I have here....they just go in but nothing happens when I push it in in order to pop it and come out,hence I have to pull them out with tweezers.

I hope you understand what I'm saying...

I'm sure they are normal sd adapters...I've been using them with the pc with no problems